Error returned when a server cannot find the requested page.
Once upon a midnight dreary, while I websurfed, weak and weary,

Over many a strange and spurious website of 'hot chicks galore',

While I clicked my fav'rite bookmark, suddenly there came a warning,

And my heart was filled with mourning, mourning for my dear amour.

"'Tis not possible," I muttered, "give me back my cheap hardcore!"

Quoth the server, "404".
by mikm May 30, 2005
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What's up with this new character limit thing, anyway? It pisses me off.
by wysiwyg August 12, 2004
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404 is an HTTP status code. When you visit a web page, your computer is requesting data from a server using Hypertext Transfer Protocol (HTTP).

Before the web page is displayed, your browser sends the web server its HTTP header. The server responds with its HTTP header, which contains the status code.

For a normal web page, the status is 200 (OK). You don't see this because the server just sends you the content of the page.

If you encounter an error, then you see the actual status code, such as 404 Not Found.

The first 4 indicates a client error. The server is saying that you've done something wrong, such as misspell the URL or request a page which is no longer there. (For comparison, a 5xx error indicates a server-side problem, which may be transient; if you try it again, it may work.)

The middle 0 refers to a general syntax error. This could indicate a spelling mistake.

The last 4 just indicates the specific error in the 40x group, which also includes 400: Bad Request, 401: Unauthorized, etc.
by johnhms July 12, 2008
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A person who is "not there" or who is not performing their function well.
Good luck getting service, that bar was staffed by a bunch of 404s.
by narcolepticdoc February 15, 2012
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webpage not at this address.
From internet error 404 - File Not Found
You step in the stream,
But the water has moved on.
This page is not here.
by mandingoe April 30, 2004
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You are seeing this definition because Urban Dictionary thought it would be a good idea to make this their 404 page!
I got the 404 error also!
by fizzeh February 19, 2005
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Someone who's clueless. From the World Wide Web error message "404 Not Found," meaning that the requested document could not be located.
"Don't bother asking him... he's 404, man."
by Zak May 3, 2003
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